1. Technical Field
The invention relates to a line head which images light beams emitted from light emitting elements with imaging lenses and an image forming apparatus using the line head.
2. Related Art
As such a line head is known the one including a plurality of light emitting elements arranged in the longitudinal direction of the line head and an optical system for imaging light beams emitted from the plurality of light emitting elements on an image plane. For example, a line head disclosed in JP-A-2-164561 (LED printer head in JP-A-2-164561) includes a plurality of LEDs (light emitting diodes) arranged in a longitudinal direction and a plurality of refractive index distribution type lenses (rod lenses (registered trademark of Mitsubishi Rayon Co., Ltd.) disclosed in JP-A-2-164561) arranged to face the plurality of LEDs. In such a line head, a light beam emitted from one light emitting element is imaged on the same position of an image plane in a superimposed manner by the respective plurality of refractive index distribution type lenses, thereby forming one spot on the image plane. A part where spots are formed in this way is exposed.